Positive position switch



Filed Nov. '7, 1957 INVENTOR. L51 Alva .5. KUYKEAIflALL Ar TORNEYS United States Patent POSITIVE POSITION SWITCH Leland S. Kuykendall, Cedar Rapids, Iowa, assignor to Collins Radio Company, Cedar Rapids, Iowa, a corporation of Iowa Application November 7, 1957, Serial No. 695,133

3 Claims. Cl. 200-67) This invention relates to switches and more particularly to a novel positive-position switch with a rapid switching action.

Existing switching mechanisms utilize the potential energy in "springs or similar devices to controlthe positive and rapid action of-the switch members. However, these existing switch mechanisms employ an in-line switch design which merely overcomes spring pressure or force to cause the rapid switching action. In these mechanisms a reduction in spring tension automatically changes the positive action qualities in addition to slowing down the switch action. This invention provides an improved positive-position snap switch which cannot be inadvertently operated even when the spring should break or exert a reduced amount of force. This is particularly important where the switch must remain in the latest selected position, thus maintaining the positive-positioning requirement.

It is an object of this invention to provide a novel switch mechanism which positively positions a switch to remain at a selected position. It is-a further object of this invention to provide such a novel switching mechanism which has precise and rapid switching action when positively operated. It is a still further object of the invention to provide such a novel switching mechanism wherein the force of the spring is not in-line with the actual switch elements, thereby eliminating possible inadvertent switch action due to the reduced force exerted by the spring.

These and other objects of the invention will become apparent when the following description is read in conjunction with the accompanying drawing consisting of five figures, wherein:

Figures l-4 are isometric representations of one embodiment of thisinvention in various sequential operations of this invention, and

Figure 5 is a side view of the same embodiment of this invention.

Referring now to the drawing, Figure 1 depicts the positive-position fast action switch of this invention at rest in switch position 1. The switch contact element 5 makes electrical contact with the selected one of the contacts 1 and 2, namely contact 1 at this instant. This contact element 5 is firmly affixed to the shaft, 6. Also aflixed to the shaft 6 is a pivot arm 7 which has a cam follower or pin 8 attached to the extremity of the arm 7 opposite the shaft 6. A plate or sector gear 14 has a plurality of gear-teeth cut' in a predetermined portion of its periphery and a predetermined cam surface 11 cut in another portion of its periphery. This cam surface 11 includes two extreme indentions It) which individually correspond in a predetermined manner to the desired positions of the contact element 5. Attached near and adjacent to the gear-tooth portion of the periphery of the sector gear 14 is a pin 17 which holds one end of the spring 9. The other end of the spring 9 is attached to the pin 8 on the pivot arm '7. Meshed with the geartooth portion of the periphery of the sector gear 14- is in-line with the motion of the pin 8.

a gear 13 which is attached to shaft 16; Also attached thus exerting additional force from the spring 9'upon.

the pin 8 and the arm 7 into the cam surface 11. When the sector gear 14 is rotated substantially, thecut of the cam surface 11 is such that the'majority of the force:

from the spring 9 is exerted into the space comprising. one of the indentions 19 in the sector gear 14 rather than directly against the cam surface 11.. This force from the spring 9 then moves the pin Switha positive and quick'rnotion into this indention 10, thereby rotating. the arm 7. This rapid switching action resultsafromthe rapid motion of the pin E5 and the arm 7 into the indention lil due to the force of the spring ,9 being Arm 7 rotates the shaft 6 in an obvious manner at this time. It is obvious that some means of fastening or holding film the shafts must be necessary. However, such a plate or fixed structure is well known to those skilled in the art and will not be described or shown herein.

A description of this invention is depicted sequentially in Figures 2-4. Figure 2 shows the beginning of the switch action where a force must necessarily be held to rotate the knob 12 and the shaft 16 in the direction shown by the arrow in Figure 2. This rotational force is normally exerted manually, but obviously may be rotated by a motor or similar power means. Rotation of shaft 16 turns the gear 13, which rotates the sector gear 14 to the position shown in Figure 2. In this'position, pin 8 has commenced to ride upon the cam surface 11 as shown in the figure. Figure 3 shows the operation of this invention at a subsequent point of the rotation of the sector gear 14. The spring 9 is now extended so that a much greater potential force exists between the ends of the spring 9. So far, the rotation of the knob 12 has resulted in no motion whatsoever of the contact element 5.

As the knob 12 continues to rotate the sector gear 14, the pin 8 passes over the cam surface 11 so that the direction of movement of the pin 3 is into one of the cut-out portions or indentions 10 in the sector gear 14. At this point, the potential energy stored in spring 9 operates in-line with the cam surface 11 and the motion of pin 8 to rapidly pull the pin 8 to the position shown in Figure 4. The pin anchoring one end of spring 9 is pulled by the action of spring 9 as close as possible to the pin 17 on th sector gear. The motion of pin 8 rotates arm 7 and thus shaft 6, which causes the contact element 5 to be rapidly rotated from switch position 1 to switch position 2. As is obvious from Figures 2-4, if the knob 12 is now rotated in the direction shown by the arrow in Figure 4-, the steps shown in Figures 24 will be repeated in an opposite sense. Spring 9 will once again be given a considerable amount of potential energy, which will be used to rapidly reposition the contact element 5 back to switch position 1.

Figure 5 is a side view of this invention and is presented to show the approximate relationship of the various elements. As shown in Figure 5, the spring 9 is at an intermediate position between switch positions for approximately the same point in the sequential operation as depicted in Figure 3.

Although this invention has been described with respect to a particular embodiment thereof, it is not to be so limited as changes and modifications may be made Patented Oct. 27, 19591:

therein which are within the full intended scope of the invention as defined by the appended claims.

What is claimed is:

1. A bi-directional positive position rapid action switch comprising a sector gear including a first portion formed with gear teeth, a pair of peripheral indentations formed in said sector gear adjacent the end of the first portion, a cam surface between the indentations which has a radius smaller than the tooth portion, a first shaft, gear means afiixed to said first shaft and engaging said sector gear, a rotating means afiixed to said first shaft, 2. second shaft, switching means connected to said second shaft, a pivot arm connected to said second shaft, a cam follower affixed to said pivot arm and in engagement with the cam portion of said sector gear, a spring biasing means for retaining said follower against said cam until the limit of said cam is reached wherein said follower snaps across one of the indentations thereby causing rotation of the switching means whereby said cam follower will rotate operating said switching means in response to said spring bias when the edge of said arcuate cam surface is removed.

2. A positive position rapid action switch comprising the device as claimed in claim 1 wherein said spring biasing means includes a spring with one end attached to said gear sector and the other end attached to said cam follower pivot arm.

3. A bi-directional positive position switch comprising, a plate, said plate including an arcuate cam, a first rotatable shaft, one end of said shaft attached to said plate, a second rotatable shaft, a switching means attached to said second rotatable shaft, a cam follower arm attached to said second rotatable shaft, a cam follower attached to said cam follower arm, said cam follower engaging the arcuate portion of said arcuate cam sector, a biasing means including a pin and a spring means, said pin attached to said plate and substantially diametrically opposite the center of said arcuate cam sector, and said spring means attached to said pin and said follower, whereby said cam follower will rotate, operating said switching means in response to said spring bias when the restraining edge of said arcuate cam surface is removed.

References Cited in the file of this patent UNITED STATES PATENTS 836,019 Du Bois Nov. 13, 1906 1,856,092 Ebeling May 3, 1932 2,253,183 Le Count Aug. 19, 1941 ,788,410 Terry Apr. 9, 1957 

